Polycrystalline diamond materials having improved abrasion resistance, thermal stability and impact resistance

Abstract

PCD materials comprise a diamond body having bonded diamond crystals and interstitial regions disposed among the crystals. The diamond body is formed from diamond grains and a catalyst material at high pressure/high temperature conditions. The diamond grains have an average particle size of about 0.03 mm or greater. At least a portion of the diamond body has a high diamond volume content of greater than about 93 percent by volume. The entire diamond body can comprise high volume content diamond or a region of the diamond body can comprise the high volume content diamond. The diamond body includes a working surface, a first region substantially free of the catalyst material, and a second region that includes the catalyst material. At least a portion of the first region extends from the working surface to depth of from about 0.01 to about 0.1 mm.

1. A method for making a diamond construction comprising the steps of:
 subjecting a volume of diamond grains to a high pressure/high temperature condition in the presence of a catalyst material to form a fully sintered polycrystalline diamond body having a diamond content of at least 93 percent by volume; and 
 treating at least a first region of the diamond body extending from a working surface to render the region substantially free of the catalyst material while allowing the catalyst material to remain in an untreated region; 
 wherein the first region extends within the polycrystalline diamond material only to a depth of from 0.01 mm to 0.08 mm as measured from the working surface, wherein the diamond grains comprise a multimodal distribution of differently-sized diamond grains, and wherein a majority by volume of the total diamond grains have an average particle size of 0.05 mm to 0.1 mm. 
 
     
     
       2. The method as recited in  claim 1  further comprising before the step of subjecting, placing the volume of diamond grains adjacent to a substrate, wherein during the step of subjecting, the polycrystalline diamond body is integrally joined to the substrate. 
     
     
       3. The method as recited in  claim 1  further comprising before the step of subjecting, heating the volume of diamond grains to form graphite. 
     
     
       4. The method as recited in  claim 1  wherein the first region extends within the polycrystalline diamond material a depth less than 0.05 mm. 
     
     
       5. The method as recited in  claim 1  wherein the first region extends within the polycrystalline diamond material a depth of less than 0.03 mm. 
     
     
       6. The method as recited in  claim 1  wherein the first region extends within the polycrystalline diamond material a depth of 0.04 to 0.07 mm. 
     
     
       7. The method as recited in  claim 1  wherein a minority of the diamond grains has an average particle size of less than 0.03 mm. 
     
     
       8. A method for forming a diamond construction comprising the steps of:
 subjecting a volume of diamond grains to a high pressure/high temperature condition in the presence of a catalyst material to form a polycrystalline diamond body, wherein the diamond grains comprise a multimodal distribution of differently-sized diamond grains, and wherein a majority by volume of the total diamond grains have an average particle size of 0.05 mm to 0.1 mm, wherein a substrate is positioned adjacent the volume of diamond grains and during the step of subjecting is attached to the polycrystalline diamond body; and 
 treating a region of the polycrystalline diamond material to render it substantially free of the catalyst material while allowing the catalyst material to remain in an untreated region; 
 wherein the treated region extends within the polycrystalline diamond material a depth of from 0.02 to 0.05 mm from an outer surface of the diamond body. 
 
     
     
       9. The method as recited in  claim 8  wherein a minority of the diamond grains have an average particle size of less than 0.03 mm. 
     
     
       10. The method as recited in  claim 9  wherein the minority of the diamond grains have an average particle size of less than 0.02 mm. 
     
     
       11. The method as recited in  claim 8  wherein before the step of subjecting, heating the diamond grains to form graphite. 
     
     
       12. The method as recited in  claim 8  wherein the polycrystalline diamond body has a diamond content of from about 93 to 99 volume percent. 
     
     
       13. The method as recited in  claim 8  wherein the diamond body has a diamond content of at least 93 percent by volume. 
     
     
       14. The method as recited in  claim 8  wherein a minority of the diamond grains has an average particle size of less than 0.03 mm. 
     
     
       15. A method for making a polycrystalline diamond material comprising:
 combining a volume of diamond grains with a volume of catalyst material to form a mixture, wherein the diamond grains comprise a multimodal distribution of differently-sized diamond grains, and wherein a majority by volume of the total diamond grains have an average particle size of 0.05 mm to 0.1 mm; 
 pressurizing the mixture under elevated temperature conditions to form the polycrystalline diamond material, the polycrystalline diamond material having a diamond content of at least about 93 percent by volume and having a working surface; and 
 treating a first region of the polycrystalline diamond material to render it substantially free of the catalyst material while allowing the catalyst material to remain in an untreated region; 
 wherein the first region extends within the polycrystalline diamond material a partial depth therein from 0.04 to 0.07 mm from the working surface. 
 
     
     
       16. The method as recited in  claim 15  wherein the catalyst material is selected from the group consisting of metals from Group VIII of the Periodic table. 
     
     
       17. The method as recited in  claim 15  further comprising placing the mixture adjacent to a substrate, wherein during the step of pressurizing, the polycrystalline diamond is integrally joined to the substrate. 
     
     
       18. The method as recited in  claim 15  further comprising heating the volume of diamond grains to form graphite. 
     
     
       19. The method as recited in  claim 15  comprising using a volume of diamond grains that is greater near the working surface than a volume of grains a distance from the working surface to provide a polycrystalline diamond material having regions of different diamond content. 
     
     
       20. The method as recited in  claim 15  wherein a minority of the diamond grains has an average particle size of less than 0.03 mm.